Gemstone Photography: Fact and Fiction

Gemstone Photography, this seems to be a constant area of debate amongst the gemstone and jewelry community. Sadly, most of the information that gets relayed in these debates is just incorrect and misinformation. My goal with this article is to try and straighten out a few of the larger misconceptions and misinformation be spread around. Photography and its techniques and secrets used to be known and done only by a few that had the skill to succeed and those who could afford the equipment necessary. With the advent of the super affordable entry level digital SLRs, like the Canon Rebel series(XT, XTi, XS, XSi, etc.) and Nikon D40/60/70/80, photography became far more widespread and adopted as a hobby and a “business”. The term business is in quotations because I am using the term very loosely, because soooo many people tried, and continue to try, to jump onto the bandwagon of the photography industry. They did so with the thought that they have the equipment so now they can do the work. This is seldom the case. It is not the equipment that makes the photographer but rather the photographer that makes the equipment. But, sadly, as most anyone truly in the photography Industry can attest to, far too many think that a dSLR(digital SLR) makes them an instant professional and of course being on the internet even more folks yet pretend to be a professional and/or like they know “everything” about photography. This is where a large portion of the misinformation comes from, those that have just enough knowledge to be dangerous! Now enter the photo editing software wizards, who, most, go out and pirate a very well known professional software and use it to turn OK shots into better ones, yet another source of misinformation.

Let us start out with one of the most misunderstood issues with digital cameras, true colors. Almost all digital cameras on the market use a sensor in them based off of the Bayer sensor design, be it CMOS or CCD. Those companies like Canon, Nikon, Pentax, Olympus, Panasonic, etc. all included. The Bayer based sensor is by all senses an excellent design, but it has a few serious shortcomings and one of those happens to be accurate reproduction of colors. Every digital camera has a sensor, each sensor has on it what are called photosites, these photosites are what actually captures the digital image when the shutter opens. For this discussion, for ease of understanding, we will from here on out refer to photosites as pixels, since almost everyone is familiar with this terminology. In order to produce an image the photosites need to capture each color channel, R(red) G(green) B(blue). This is where the problem arises. The pixels on Bayer based sensors can only capture one(1) of these three colors, RGB, and not all three. But as mentioned earlier each pixel needs to capture all three(3) color channels, so how does this work you ask? Fairly simply actually. The onboard software is programmed with special algorithms(which vary by brand) which take the other two(2) color channel data from the pixels surrounding each one and interpolate the other two(2) color channels. So, say we have Pixel 1, Pixel 2, and Pixel 3, what happens is Pixel one captures R channel, whilst Pixel 2 captures G channel, and Pixel 3 captures B channel of color data. In order for Pixel 1 to complete its duties the onboard software takes the G and B color data from Pixels 2 & 3 and interpolates the “proper” G & B color data for Pixel 1. What is interpolation? I am glad you asked. Interpolation is basically guessing, the algorithms create the missing color data out of the data from the surrounding pixels and guess at what it should be. Now, while not perfect, they do do a pretty darn good job! But I am sure many of you have seen the shortcomings when you shoot an image with red, or shades of red, in it; As well as sometimes greens and shades of greens. So, now you know why most cameras on the market can not capture true colors. The only ones that can are those utilizing the Foveon sensor technology because due to their design each pixel actually captures RGB and no data is interpolated.

Another misconception is white balance and base & background colors. Not all cameras are created equally when it comes to white balance settings. Some, like the Pentax line up, have far more in depth white balance controls and settings. The great thing is, if set properly, a custom white balance will typically work just fine. The real problem is that some cameras just do not like certain light sources, for example, Canon cameras really do not work well hand in hand with GE Reveal lighting. Setting a custom white balance is a key to getting as accurate of colors as possible from your camera. This should be done using a white balance cap, card, or other tool to properly set a custom white balance. It seems many are of the thinking that as long as you set a proper white balance that the background and base colors you are shooting on do not matter, this could NOT be anymore INCORRECT! White balance plays no part in this! In order to produce accurate colors with transparent and translucent materials you MUST shoot them on a white base with a white background with NO patterns in them, period! If you shoot on any other colors with or without patterns your colors, tones, depth, and saturation will not be true to life. A prime example is how swindlers used to take lower grade color/saturation/tone rubies and display them on yellow papers instead of white ones, because the yellow color will enhance the red of the rubies. Same principle is used by many TV gemstone sellers who most always show blue gemstones, like tanzanite, on maroonish backgrounds, why, because it enhances the blue of the gemstones. Dark and/or black backgrounds intensify the saturation and tone and depth of the color in any gemstone. A white balance is used to “calibrate” your camera to the light source being used, not the base & background colors and how they affect the gemstone colors.

Now, let us touch on metering. Most cameras have numerous metering modes, even though many users do not even know about them, lol. It pays to read the manual, hehe. The best mode to use for shooting gemstones is Spot metering. If your camera does not have this mode then choose center weighted average or similar. Metering will lead to proper exposure, proper exposure will lead to truer colors, tones, etc. in your images.

Another misconception out there is that no matter what images on the internet can never be totally accurate. This used to be true, but has since become a piece of misinformation as well. Many browsers currently support the reading of color profiles embedded in image files. If the photographer has a properly hardware calibrated computer and setup the shot properly and embeds the color profile of his PC into the image file the image can be viewed in one of these browsers just as it was on the photographer’s PC. Safari browser for PC & MAC as well as FireFox support embedded color profiles.

A big thing is on the internet you get, the “my friend said this”, “my web designer said this”, “my dog said this”, etc, lol. In most cases none of these “my {whatever} said this” are correct. Why? Because in almost all cases these folks are not photographers nor trained in photography but at best are those who know just enough to be dangerous!

As for photohop and/or editing of images, this is another often misunderstood topic. Keep in mind ALL digital cameras edit the picture inside the camera with sharpening, saturation, colors, contrast, etc. at the time the picture is taken. There is NO such thing as an unedited digital image except one in RAW format. If the shooter shot the image in RAW format then the image has to be edited in a software in order to be presented properly during conversion. Images when resized for the internet also need to be edited because the resizing of the image causes it to lose a bit of sharpening and quite a bit of local contrast(which the human eye perceives as sharpening). But far too many folks use Photoshop to overly enhance an image and make it into something it is not in real life. Heavy editing is a bad thing! But don’t fall for the “I converted right from RAW so non editing” line. I hear this day in and day out in photo forums and gemstone/rock/mineral forums as well and this just is NOT true!! ALL RAW converters apply editing to an image by default, not to mention contain a full suite of tools to crop, enhance, boost saturation, sharpness, contrast, almost a full line of tools like one would find within Photoshop itself. So the possibilities are actually endless on what could have been done during RAW conversion. There are ways to use a special command line program and do a straight conversion of RAW data with NO editing and just the in camera settings at the time for ISO, white balance, etc. with everything else zeroed out for a truly unedited image, but very few folks know how to do this as it is not a normal necessity for an image processor to need to do, except for forensics and law enforcement reasons, for example.

Another often heard comment is, “those pictures look like x-rays of the stone, seeing all the way inside, they have to be faked or windowed, etc.”. This is not a correct comment/statement. Just because the table and crown facets can not be seen does not mean the image is faked or the cut is incorrect. Focal points play a large part in what will be in focus and will not be.

Also, lighting is a large key point. Proper lighting consists of full spectrum lighting calibrated to Daylight(5500K-6500K). No other type light sources should be used in order to photograph gemstones and/or jewelry unless showing the color change of a stone, of course.

In closing I want to give a list of a few things to watch out for and stay away from when shopping on the internet for gemstones and/or jewelry.

Any gemstone shot on a background or base that is any color other then white. Now keep in mind that a white background may show up in the image as a light to lt-medium grey color if the base/background was not lit.

If an image looks heavily photoshopped, it most likely is and is more then likely not a true representation of the gemstone.

If the background or base has any patterns in them this can cause inclusions and/or other “blemishes” on a gemstone to become hidden and not viewable in the picture.

Watch out for angled shots. Many times a seller will shoot a windowed stone at an angle up or down from perpendicular to the table in order to hide that window.

Beware stones that only show the table/crown and reflected facets as they can be hiding what is inside.

Remember that gemstone images are typically done under magnification and therefore many flaws or inclusions that may show up in the images may never be seen by the naked eye in person.

A gemstone image should be an accurate portrayal and NOT a piece of fine art. Multiple images is the best choice, especially with one of them being of the stone table down and one being an accurate representation, an extra fine art one is a bonus but not what is most important when considering the purchase of a gemstone on the internet.

Just because an image is good, however, does not mean it is photoshopped or the like. The seller may be a professional photographer, contract out to one, or just be good at taking pictures of his/her gemstones.

Do NOT be afraid to ask the seller for larger images if you find their pictures too small. Most will and can accommodate you with such as request. Many only supply small sized lower resolution and highly compressed images online for speed of loading and to prevent theft issues. If they refuse to send you a larger shot of the gemstone upon your request with less compression, then I would seriously consider just moving on, because there is a reason. But just because an image maybe smaller online doesn’t mean they are hiding anything, this is standard practice by Professionals who also sell images to stock photo places. Just ask them.

Always ask questions. The description should give a quality remark or even grading on the cut & polish of a gemstone. If it does not have one, as them for one with the specs of the stone in question. They should have no problems supplying this.

The color may or may not be commented about, but whether it is or is not really a concern, but ask them to give you a color code so you can be sure of the color you are seeing. There is, after all, a website that will allow them to do a basic one for free for you. If they are not aware ask then to go here: GemeSquare Lite and get you one.

If spending quite a bit of money, be sure, require a Lab Report from a known and reputable Laboratory! You may have to pay for this lab report out of your pocket and up front, not a problem and somewhat typical, but otherwise there should be no problems with them fulfilling this request unless they have something to hide.

If buying a colored diamond that is being touted as natural color, make sure it is an Origin of Color Report as well. I would want a reputable lab report as well if it is a high dollar one.

If in doubt when you receive a stone, find a local Gemologist to test it for you, or at the very list come here to us and we will do our best to help you out with your issues and how to go about rendering it in your favor.

If you think an image just looks too good, then ask for a simple snapshot of the gemstone under sunlight outside. A seller should have no issues granting your wishes so as your are polite and courteous and have genuine interest in his/her product(s).

Ask questions about the seller and the gemstone in question, is he/she a Gemologist? Has the stone been checked by a Gemologist? If so, did they attend a school for to learn their Gemology? Do they have testing equipment? What kinds/types? How was the stone tested?

Is it treated? If so, how? Be careful with coated stones & clarity enhanced stones, nothing wrong with these and they make for excellent affordably priced stones, but, special care is needed and price should reflect the treatments and level of treatments done, that is all.

Does this stone require any special care instructions and/or precautions?

Do you know the origin? Knowing the origin is typically a good thing as it means the seller at least has a little knowledge about how the gemstone got into his/her possession.

Did they cut the stone or have it cut? Is it a USA cut(best cuts out there if the cutter knows his job)? Is it native cut? If so plan on figuring in recutting costs in many cases. Is it commercially cut? If so, what level/quality? If lower and/or poor, again, figure on recutting fees.

Do they know the entire “travel” line of the gemstone? As in, do they know whose hands it has went through before getting to them? This is important because the less people it has gone through the better chances there are no issues lost in transit that you should know as a buyer, like treatments.

Ask about the polish? Does it look good? How about under a 10x loupe?

Ask about facet junctions, keel lines, etc. and if there are any chips or nicks on them. As long as not able to be seen through the table, these are not really a big deal, but price should be lower accordingly.

Always make sure the seller/vendor has a good return policy just in case things are misrepresented!

In summation, make sure your information comes from a source that knows what they are talking about! Do NOT fall prey to those purposely trying to deceive, or just those spreading misinformation because they are “pretending” to be/know something they are not/do not know. A good gemstone picture will properly display colors and a general appearance of the gemstone, but the stone should always look better in person because a still image can NOT begin to capture the scintillation and/or dispersion of a gemstone! If the stone looks better in then image then in person, make sure to inform the vendor/seller, speak up and make them fix the issues.

Here are a few examples:

Image 1 here is the image by the vendor with normal editing done after resizing, otherwise as it came out of camera. Notice the background colors, even though it was shot on a white base and white background. Any darker background and it would not have been a white one but instead a grey or black one which would enhance the stone.:

This is the same stone shot and slightly edited to make it even truer to what one sees in hand. Notice the background colors, even though it was shot on a white base and white background. Any darker background and it would not have been a white one but instead a grey or black one which would enhance the stone.

Now, lastly, here we have the same stone and shot as the one directly above, but we have heavily edited the image in photoshop to give it that awesome artsy look many are turning to to try and accurately portray their stones. As you can see, it does nothing more then greatly enhance the appearance in a way that makes it look even better then how it is in hand. Notice the deeper tones and better saturation and even a slightly darker and better tone of green. One dead giveaway is the darker background, although in this case it was photoshopped in, but you can see what even that does to the stones appearance. Taken on a background of color it would have been even more phenomenal looking, but not a realistic portrayal at all.

And lastly we have an image shot high key style where the actual background and base are lit an exposed for as well as the gemstone itself. This base and background are the same as the others above, believe it or not, which is why I stated light grey to lt.med. grey and it is still probably a white background Thanks to Gems By Jennifer for allowing the use of her images in this article.

FYI, the above images are even quickie shots and edits, aside from the heavily edited one, they were all less then 3mins from shooting time to ready for web time(not including transfer from camera to PC of course). So imagine what one could do to enhance if they took the time! I spent less then 3 mins total on the heavily edited shot! Most people will spend much longer editing an image.

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Canadian Institute of Gemmology
One of the objectives of this website is to provide gemmologists from around the world with an opportunity to exchange information in a fast and efficient way. At the same time GEMOLOGY WORLD™ can serve as a resource for the general public to learn more a